Did the ancient Jews believe that Satan never rebelled against God and is not evil? Is the idea that Satan rebeled just a Christian idea?
I am a bit confused about your question. Is there anyone who has suggested differently? Going all the way back to Genesis 2, Satan is a figure of evil. I have never heard of a proposal that the Jews did not see Satan as anything other than evil. If everything God created is good (as implied by Genesis 1:31), then evil can only be the result of rebellion. I know of no Jew who saw this differently. The battle between Satan and his angels is one between good and evil in Daniel. My guess is that your question is coming from somewhere. Can you tell me the source of your question?
Some have argued that the Jews did not believe in Satan in the sense that Christians do. This is a possibility. Some Jews may have had a less-well-developed idea of a personal evil “person” who we call Satan. However, as far as I know, to the extent that we can say the Jews believed in Satan at all, their conception of Satan was similar to that of the New Testament.
I am sorry for a vague answer.